Environmental Engineering Reference
In-Depth Information
There are opportunities all around the world to produce shale energy, and the United States is a pioneer.
There are estimated to be far more natural gas supplies in what are called methane hydrates, natural gas
deposits in frozen form, which exist at the bottom of the ocean.
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Thus the potential supply of natural gas
could extend many centuries, at least.
At the same time, advances in compressing and liquefying natural gas are making it more prominent as
a fuel and make it easier to transport around the world. This is the source of opportunities and controver-
sies for LNG (liquefied natural gas) terminals.
Gas can also be turned into fuel oil and methanol, and it powers vehicles in compressed or liquefied
form. Still, when it comes to transportation, nothing can yet compete with what is far and away the world's
leading transportation fuel: oil.
OIL
Oil is the most coveted (and controversial) fuel in the world because it is almost eerily engineered by nat-
ural processes, not just for cheapness, not just for reliability, not just for scalability, but also for another
characteristic crucial to a functional civilization:
portability.
Oil is an ultraconcentrated form of energy—liquid energy—so it's ideal for any moving vehicle. Every
portable power source needs to carry its fuel with it, which means that size and weight are of para-
mount consideration. Oil, in effect, has the ultimate strength to weight ratio. A gallon of gasoline has
31,000 calories—the amount of energy you use in
fifteen days
. Oil can be refined into stable, potent liquid
fuels—gasoline, diesel, and jet fuel.
Oil's dominance as
the
transportation fuel has gone hand in hand with the development of mobile en-
gines: the gasoline engines in most cars, the diesel engines powering semitrucks and global shipping, and
the jet engines powering aircraft all eat oil fuel.
Oil is used for the vast, vast majority of transportation—93 percent in the United States.
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Other tech-
nologies struggle to mimic it.
Oil's value leads to continuous large investments in exploration and extraction technology. Whereas oil
deposits were once completely invisible to industry, today modern imaging, called 3D seismic imaging,
can get us a far clearer idea of what's going on below the surface and how it changes over time. We can
get oil out of hard rock (shale oil). In oil sands, we've created technology that acts as a ground decongest-
ant—releasing oil from the sands that have held it in place for decades.
Portability is valuable for many reasons. Personally, oil is the fuel of freedom—the fuel that liberated
Americans to go where they want, when they want. Economically, oil is the fuel of trade. Our entire stand-
ard of living depends on
specialization
—on people doing what they do best, wherever they are, and then
being able to cheaply move their products to those who most need them. The higher the price of portable
power, the slower the world economy moves.
In the future, it is quite possible that battery-powered vehicles will replace oil-powered vehicles for
certain purposes. The limits are based on the energy concentration or energy density of the batteries; for
example, the Tesla Roadster battery has an energy density that is 107 times
less
than gasoline—though
the battery's electric motor can convert more than twice as much of that energy into usable energy as the
engine in a gasoline-powered car, so in practice the Tesla battery might be 35 times less dense.
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